Bait box

ABSTRACT

A bait box assembly has a bait box ( 10 ) and a base member ( 30 ) which can be secured to a support surface. The bait box has a lid ( 12 ) which can be moved between a locked and closed position and an unlocked and open position. The base member ( 30 ) and bait box ( 10 ) have interengageable formations ( 36, 36′, 20, 21 ) which secure the bait box ( 10 ) to the base member. ( 30 ). The bait box ( 10 ) can only be released from the base member ( 30 ) when the lid is in the unlocked and open position.

The present invention relates to bait boxes, in particular bait boxesfor rodents.

Bait boxes for rodents are used widely in many areas where the issue ofhygiene is important. For example, they are used in the food industry,whether it be in factories where food production is taking place, or inrestaurants or other food outlets where food is stored and prepared.Bait boxes have also been used in the healthcare industry, for examplein hospitals, to prevent the risk of ingress of infection by means ofrodents in to relatively clean or sterile areas and monitor rodentinfestation.

Bait boxes are either set down on, or fixed to, a support surface andare provided with openings of a predetermined size to allow access tothe bait by selected rodents. The boxes may be fixed directly to thesupport surface or by means of a support plate or bracket. The boxes arearranged to hold some form of bait which attracts small rodents to feedin the box. The bait often includes a rodenticide which the rodentingests and will lead to the death of the rodent, possibly quickly, butusually some time (for example a matter of days) later.

In order for bait boxes to be effective they must be positioned inlocations where rodent infestation is most likely to occur, for examplenear food production, preparation or storage areas. Bait boxes can bepositioned on support surfaces such as the frames of conveyor systems oron the floor of a kitchen or a food store. Rodent infestation ismonitored on a regular basis in such areas by a hygiene assistant orpest control operative examining the contents of the box to check forsigns that the bait has been eaten in any way. In this regard, due tothe health risk posed by boxes which have been visited by rodents andbait which has been eaten it is vital that these boxes remain locked andin a fixed position.

In many industrial or commercial establishments where bait boxes areused, several boxes can be required to provide an adequate rodentmonitoring network. Due to the nature of these establishments boxes aresometimes positioned in locations which are relatively difficult toreach for a pest control operative to open the box in an adequate mannerand view the contents carefully. Moreover, due to the relatively smallnature of the boxes they are sometimes difficult to open and pestcontrol operatives may, when faced with many of these boxes to check,not inspect each bait box carefully or even open them at all and simplyassume that the contents are intact. However, if the bait inside eachbox is not carefully checked there exists the possibility that thenumber of rodent incidents is not monitored properly or that bait boxesare left empty of bait. In this situation, due to the relatively shortgestation periods of many rodents, the rodent population can quitequickly get out of hand leading to an explosion of the rodent populationwhich may prove costly and difficult to control.

Furthermore, many bait boxes are simply placed on the ground or onstationary parts of machinery leaving them vulnerable to being knockedor kicked out of position. It is vital that pest control operatives areaware of the position of the boxes in order for them to carry out aneffective monitoring regime. Losing boxes is also highly undesirablegiven the potential for the spread of disease from bait or boxes whichhave been visited by rodents.

Unfortunately, there have been instances where malicious workers havedeliberately tampered with bait boxes by picking them up and throwingthem directly into a food production areas or vessels such as vats. Thiscreates a health risk to workers, machinery and food in production whichmay require expensive cleaning or fumigation processes and can result inmachine downtime which has knock-on effects to production and ultimatelyprofits. Therefore, there exists a great need for bait boxes which canbe secured at a monitoring location in a tamper-resistant manner.

In one aspect, the present invention provides a bait box assemblycomprising a bait box and a base member which can be secured to asupport surface, the bait box having a lid which can be moved between alocked and closed position and an unlocked and open position, in whichthe base member and bait box have interengagable formations which securethe bait box to the base member, and in which the bait box can only bereleased from the base member when the lid is in the unlocked and openposition.

Allowing release of the bait box from the base member only when the lidof the bait box has been moved to an unlocked position preventsaccidental release of the bait box from the base member. The fact thatthe box must be unlocked and opened before it can be separated from itsmounting makes the box more tamper resistant. Moreover, positive lockingmeans for the lid prevents unwarranted access to the box and stopsmiscreants tampering with it and detaching the bait box from itsmounting means.

Preferably, the interengageable formations comprise a plurality ofprojections on the base member which are received by correspondingapertures in the base compartment.

Conveniently, at least one of the projections can be displaced relativeto the base member.

In preferred embodiments, the bait box can be released from the basemember by displacing the at least one projection relative to the basemember, moving the bait box relative to the base member, and separatingthe bait box and base member.

The base member may be a planar element which can be secured to asupport surface. Most preferably, the base member is substantiallyL-shaped.

An embodiment of the present invention will now be illustrated, by wayof example only, in the following figures in which:

FIG. 1 shows a plan view of a bait box of the present invention in anopen position;

FIG. 2 shows a front elevation of the bait box shown in FIG. 1 as viewedin the direction of arrow A;

FIG. 3 shows an inverted side elevation of the lid of the bait box asshown in FIG. 1 as viewed in the direction of arrow B;

FIG. 4 shows a side elevation of the bait box shown in FIG. 1 as viewedin the direction of arrow C, with the box in a closed configuration;

FIG. 5 shows a plan view of a base plate of the present invention;

FIG. 6 shows a front elevation of the base plate as shown in FIG. 5 asviewed in the direction of arrow D; and

FIG. 7 shows a side elevation of the base plate as shown in FIG. 5 asviewed in the direction of arrow E.

The bait box 10 shown in FIG. 1 consists of a base compartment 11 and alid 12 hinged along one edge 13 of the compartment. The lid 11 has twolocking projections 14 which have hooks at their ends for engagingcorresponding locking receptacles 15 on the base compartment 12 to locklocking the lid and compartment together. A key (not shown) can be usedto move the projections 14 out of locking engagement with the lockingreceptacles 15.

In use, small rodents enter the locked bait box through entrance holes16, 17 in the sides of the base compartment. The rodents are attractedinto the bait box by blocks of bait of variable sizes which sit in baitreceiving frames 18. The bait not shown is normally laced with arodenticide which is ingested by the rodent. In most cases therodenticide is arranged to kill the rodent up to several days afteringestion/exposure therefore the death of the animal usually occursoutside the bait box. Asymmetric baffles 19 define a gap which allowsthe rodent to pass into the feeding area but prevent people,particularly children, from gaining access to the bait by poking fingersor elongate instruments in to the base compartment through the entranceholes 16, 17.

The bait box 10 is mounted onto an L-shaped base plate 30 which consistsof a base 31 which receives the base of the bait box 10 and a sideflange 32 which abuts against a side of the bait box. The base plate 30can be fixed to a support surface not shown by means of a slot 33 in theside flange 32 or a screw not shown through an aperture 34.Alternatively, any suitable fixing method such as an adhesive may beused to secure the base plate 30 to a support surface.

The base plate 30 and bait box 10 can be locked together by means of aseries of locating studs or pins 36, 36′ on the base plate 30, which fitthrough a series of locating apertures 20, 21 on the base of the baitbox, and a press stud or tab 35 having a protrusion 38 which can bemoved into and out of engagement with an edge 20′ of locating aperture20.

To secure the bait box 10 to the base plate 30 the bait box ispositioned on the base plate in such a manner that two pins 36 protrudethrough a pair of generally circular apertures 21 and another pin 36′protrudes through a generally square aperture 20. As best shown in FIGS.5 and 7, a tab 35 is connected to the base 31 of the base plate 30 alongone edge 39 of the tab 35. The body 37 of the tab 35 is thinner incomparison with the base 31 and upon depression of the protrusion 38 isflexible enough to be bent downwards. When the protrusion 38 isdepressed, the bait box 10 may be translated with respect to the base31, bringing the flats 40 on the sides of the studs 36, 36′ intoengagement with the flats 23 of apertures 21 and flats 22 of aperture20. Upon release of the tab 35, the protrusion 38 prevents movement ofthe bait box 10 with respect to the base 31.

To release the bait box 10 from the base plate 30, an operator must usea key not shown to bring the locking projections 14 out of lockingengagement with the locking receptacles 15. The lid 12 can then beopened and the operator can access the tab 35. By depressing theprotrusion 38 towards the base 31 of the base plate 30, the protrusion38 is moved beneath an edge 20′ of aperture 20 and out of engagementwith that edge of aperture 20; The bait box can then be removed from thebase plate 30 by simply sliding the bait box with respect to the fixedbase plate bringing the flats of the studs 36, 36′ out of engagementwith the flats 23 of the generally circular apertures 21 and the flats22 of the generally square aperture 20. The box can then be lifted awayfrom the base plate for closer inspection or to refill bait.

1. A bait box assembly comprising a bait box and a base member which canbe secured to a support surface, the bait box having a lid which can bemoved between a locked and closed position and an unlocked and openposition, in which the base member and bait box have interengagableformations which secure the bait box to the base member, and in whichthe bait box can only be released from the base member when the lid isin the unlocked and open position.
 2. An assembly as claimed in claim 1,in which the interengageable formations comprise a plurality ofprojections on one of the base member and the bait box, and a pluralityof corresponding apertures in the other of the base member and the baitbox, in which the projections can be received.
 3. An assembly as claimedin claim 1, in which at least one of the apertures has a keyhole shapein which the transverse dimension of the aperture is greater at one endthat at its opposite other end, and in which the correspondingprojection has a head portion and a narrowed neck portion between thehead portion and the bottom of the projection, in which the transversedimension of the aperture at the said opposite other end is greater thanthe transverse dimension of the neck portion and less than thetransverse dimension of the head portion.
 4. An assembly as claimed inclaim 3, which includes a locking projection which, when received in itscorresponding aperture, prevents the bait box and the base plate frombeing slid relative to one another, so that the narrow neck projectionis retained in the said opposite other end of the keyhole shapeaperture.
 5. An assembly as claimed in claim 3, in which there are atleast three projections, of which the locking projection is locatedapproximately midway between two opposite edges of the box.
 6. Anassembly as claimed in claim 2, in which the or each projection isprovided on the base plate and the corresponding apertures are providedin the base of the bait box.
 7. An assembly as claimed in any one of thepreceding claims, in which the base member is substantially L-shaped, inwhich one limb of the “L” is arranged to engage the base of the bait boxand the other limb of the “L” is arranged to engage a side wall of thebait box.